refactor: rename lib/ to core/ for clearer core-module separation

Rename the top-level lib/ directory to core/ so the project root
immediately communicates which code is core platform and which lives
in modules/. PHP namespaces (MintyPHP\*) are unchanged — only the
Composer PSR-4 path mapping moves from lib/ to core/.

Module-internal lib/ directories (modules/*/lib/) are untouched.

Updated across the full stack:
- composer.json PSR-4 mapping
- bootstrap entry points (web/index.php, bin/*, tests/bootstrap.php)
- tooling configs (phpstan.neon, phpunit.xml, php-cs-fixer)
- 26 architecture contract tests
- enforcement-policy, guard-catalog, quality-gates
- all documentation (CLAUDE.md, README, 25 docs/, .agents/skills/)
- bin/qa-extended.sh search paths
- .claude/settings.local.json permission paths

Workflow: .agents/runs/CORE-LIB-RENAME-001/ (Analyst → Planner →
Executor → Code Review (4 findings fixed) → Security Review →
Acceptance Test → Finalizer)

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

core/App/Module/ModuleClassResolver.php

@@ -0,0 +1,50 @@
+<?php
+
+namespace MintyPHP\App\Module;
+
+use MintyPHP\App\AppContainer;
+
+/**
+ * Resolve module-declared classes from DI first and only fall back to direct
+ * instantiation when the class is not container-bound and has no required
+ * constructor arguments.
+ */
+final class ModuleClassResolver
+{
+    public static function resolve(AppContainer $container, string $class): ?object
+    {
+        $class = trim($class);
+        if ($class === '') {
+            return null;
+        }
+
+        if ($container->has($class)) {
+            try {
+                $resolved = $container->get($class);
+                return is_object($resolved) ? $resolved : null;
+            } catch (\Throwable) {
+                return null;
+            }
+        }
+
+        if (!class_exists($class)) {
+            return null;
+        }
+
+        try {
+            $reflection = new \ReflectionClass($class);
+            if (!$reflection->isInstantiable()) {
+                return null;
+            }
+
+            $constructor = $reflection->getConstructor();
+            if ($constructor !== null && $constructor->getNumberOfRequiredParameters() > 0) {
+                return null;
+            }
+
+            return $reflection->newInstance();
+        } catch (\Throwable) {
+            return null;
+        }
+    }
+}